on a cold start the temp gauge needle goes to a little above 1/2.the gauge moves a little when producing heat.no fluid leakage and good heat.changed senser near the top radiator hose.no change.can you tell me the next part and location?
Then the problem is most likey with the gauge itself.
Tester
I don’t see what the problem is. The needle goes to 1/2 way and you have heat?
It’s a 14 year old car that the heater works and the car doesn’t overheat. Leave well enough alone before you break something.